This invention pertains to an improved metal plate for mounting a fuel pressure regulator on a fuel injection rail assembly of an internal combustion engine. More specifically, it relates to a fuel regulator mounting plate which has an elongated tubular nipple integrally formed by a stamping process from a flat strip of sheet metal stock.
Fuel pressure regulators are being redesigned in order to improve their fuel connections and thereby make them easier and more economical to install on a fuel rail. The currently preferrred regulator design has a plug-in type fuel connection for its high pressure supply side and a less pressure resistent connection in close proximity thereto for its lower pressure fuel return side. The male portion of the high pressure connection protrudes from the pressure regulator and is sufficiently long to accommodate two axially spaced apart "O"-ring seals required to produce an effective seal at the pressure involved. The axial length required for a corresponding female portion of the high pressure connection located on the mounting plate was such that it could not be formed as an integral part of the mounting plate by state-of-the-art stamping processes. It would have to be made as a separate tubular nipple and attached to the plate. The separate steps of manufacturing a nipple element and then attaching it to a regulater mounting plate would add significantly to the cost of a completed plate. The requirement of having an uninterrupted smooth surface on the inside of the junction of the plate and nipple presented manufacturing problems. It was essential to have this smooth uninterrupted surface to prevent damage to the "O" ring seals when the pressure regulator was being inserted into the nipple. The maximum protruding length of an extruded tubular nipple formed by state-of-the-art stamping processes under ideal conditions was twice the thickness of the stock. Accordingly, when a longer than normal extruded nipple was required, it could only be produced by increasing the thickness of the stock, which in the instant case was undesirable. Another limitation of state-of-the-art stamping processes was that in plastically forming a projecting nipple of maximum length the surrounding sheet stock within a radius equivalent to three times the thickness of the stock was affected and as a result no formed feature could be located within this distance.
Accordingly, it is a general object of this invention to provide an improved fuel regulator mounting plate of simplified construction that is easy and economical to produce repeatedly with precision.
It is another object of this invention to provide a one piece fuel regulator mounting plate having an elongated tubular nipple integrally formed by a stamping process from planar metal stock of minimum thickness, wherein the projecting length of the nipple is more than two times the thickness of the plate stock.
It is yet another object of this invention to provide an improved fuel regulator mounting plate which has an integrally formed elongated nipple located in close proximity to another formed feature in the plate.